1. Field of the Invention
The present invention relates to screws with function of screwdriver, and more particularly to screws capable of acting as either fasteners or screwdriver.
2. Description of Related Art
It is known that the screws are widely applied in the hardware, machinery, furniture, appliances and etc. to fasten assembled parts. In order to allow the screws to perform fastening jobs, a screwdriver is essential; due to many types and sizes of the screws, it is necessary to prepare many screwdrivers in different specifications and sizes for the corresponding screws. In fact, the screws currently have several tens types and sizes available on the market, and it is hard to offer the screwdrivers corresponding to the screws completely. Especially, many products use screws with unique specification, and it is very difficult for the consumers to find a right screwdriver. Therefore, there are following puzzles the consumers usually meet:
1. The screwdrivers are too large or too long to be used.
2. The screwdrivers are too small or too short to apply a force.
3. Although the size of certain screwdriver matches a specific screw, the screwdriver slot provided on the screw cracks at the time of the screwdriver being exerted a force to the screw, and it results in the screwdriver slipping off; under the circumferences, the screw is jammed there and unable to move forward or backward such that it leads to the fastened parts being either insufficiently fastened or not detachable.
4. Due to restriction of space available for the assembled product, the axial line of the screwdriver is often unable to coincide with the axial line of the screw even if the tip end of the screwdriver has inserted in the screwdriver slot of the screw; as a result, it may derive problems such as the assembled parts being not tightened or detached properly.